As was mentioned it's better not to overgrease ball bearings. They have a small surface area of contact and don't require much grease. Plus, being a bearing used for high speeds, more grease will cause the problems mentioned above.
"packing" bearings is mainly for tapered roller bearings. They have a much larger contact area and both require, and can handle, larger amounts of grease. Think about automotive wheel bearings from the old days. Pack lots of grease in, then clean & repack every few years. Now sealed ball bearings are used, and most last well in excess of 100k miles before needing attention. That isn't to say ball bearings are better...just that they need attention less often, and constant greasing isn't required. Properly cared for tapered roller bearings can actually far outlast ball bearings because they have adjustability, cleaning & regreasing is an option, and they can handle higher loads. But they have gone away because people want something they don't have to fool with...ignore them until they need replacing.
That should be remembered when installing tapered bearings in a steering head. Every couple years they should be disassembled, cleaned, repacked, and adjusted properly. They should last the life of the bike if that is done.
